1. Field
The embodiments of the inventive concept relate to methods of forming a semiconductor device, and more particularly, to methods of forming an impurity diffused region and a gate structure in a semiconductor device.
2. Discussion of Related Art
A semiconductor device, such as image sensor, has been fabricated by including a photodiode in a semiconductor substrate and a gate structure on the semiconductor substrate. The photodiode may convert natural light received from the exterior of the image sensor into an electrical signal. The gate structure may be disposed adjacent to the photodiode, and may exhibit electrical characteristics of the image sensor using electrical signals of the photodiode.
During a process for manufacturing a semiconductor device, the photodiode may be formed after formation of the gate structure. The photodiode may be formed by implanting impurity ions into the semiconductor substrate using the gate structure as a mask. Thus, the photodiode may be influenced by a profile of the gate structure. Also, the profile of the gate structure may be influenced by the process environment for forming the gate structure.
In the event that the gate structure has an inadequate profile, the photodiode, being influenced by the profile of the gate structure, may have an inadequate junction profile that does not meet a wanted range. An inadequate junction profile of the photodiode may deteriorate electrical characteristics of the gate structure during operation of the semiconductor device. The photodiode and the gate structure may also deteriorate electrical characteristics of the semiconductor device. Also, if the semiconductor device is disposed in an information processing system, the information processing system may malfunction due to the deterioration of electrical characteristics of the semiconductor device.